1. Field of the Invention
The present invention relates to a spring load adjusting device for cushioning equipment.
2. Description of Relevant Art
There has been proposed, for example, by Japanese Utility Model Application Lay-Open Print No. 53-5948, a spring load adjusting device for cushioning equipment of a type in which a spring seat of a coil spring of an oil damper is slidably fitted on the outside circumference of a damper cylinder thereof and the spring seat is slidably moved with a hydraulic pressure supplied from a tank installed separately from the cylinder, thereby changing the set length of the coil spring to adjust the spring load thereof. The spring load adjustment device comprises the tank which is composed of a cylinder, a piston slidably fitted in the cylinder and an adjust screw extended from the piston outwardly of the cylinder and advanceably and retreatably screwed in a cap of the cylinder.
In such a spring load adjusting device, however, an adjust screw is exposed outside of a cylinder, thus marring the appearance. Further, there is a threaded portion exposed outside of the cylinder, which is disadvantageous in that dust and the like may adhere thereto.
The present invention has been achieved to effectively solve such problems in conventional spring load adjusting devices.